U.S. patent number 7,843,310 [Application Number 11/652,025] was granted by the patent office on 2010-11-30 for power management systems, methods, and programs for in-vehicle devices.
This patent grant is currently assigned to Aisin AW Co., Ltd.. Invention is credited to Hiroyuki Asai.
United States Patent |
7,843,310 |
Asai |
November 30, 2010 |
Power management systems, methods, and programs for in-vehicle
devices
Abstract
An in vehicle device transfers connection information to a power
management device, the connection information indicating whether
the in-vehicle device can communicate with the power management
device. The in-vehicle device either transfers condition
information to the power management device, the condition
information indicating that the in-vehicle device is ready for
turning off, or sets the in-vehicle device to not communicate with
the power management device when a predetermined condition is met,
the predetermined condition indicative of an inability of the
in-vehicle device to transfer information to the power management
device. The power management device requests the connection
information from the in-vehicle device and requests the condition
information from the in-vehicle device. The power management device
determines that the in-vehicle device is ready for turning off when
both the connection information and the condition information have
been received from the in-vehicle device, or no connection
information has been received from the in-vehicle device because
the in-vehicle device has been set to not communicate with the
power management device.
Inventors: |
Asai; Hiroyuki (Okazaki,
JP) |
Assignee: |
Aisin AW Co., Ltd. (Anjo,
JP)
|
Family
ID: |
37912486 |
Appl.
No.: |
11/652,025 |
Filed: |
January 11, 2007 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20070176731 A1 |
Aug 2, 2007 |
|
Foreign Application Priority Data
|
|
|
|
|
Jan 13, 2006 [JP] |
|
|
2006-006527 |
|
Current U.S.
Class: |
340/3.1; 701/36;
340/693.1; 700/22; 307/10.1; 340/4.3 |
Current CPC
Class: |
H04L
12/12 (20130101); Y02D 50/40 (20180101); Y02D
30/50 (20200801) |
Current International
Class: |
G05B
23/02 (20060101); B60L 1/00 (20060101); G05B
11/01 (20060101); G05B 19/02 (20060101); G05B
23/00 (20060101); G06F 7/00 (20060101) |
Field of
Search: |
;701/36 ;713/300,320,324
;700/286,22 ;307/9.1,10.7,10.1
;340/693.1,3.1,501-506,521-527,825.22-825.25,3.51 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
0 140 814 |
|
May 1985 |
|
EP |
|
0 515 042 |
|
Nov 1992 |
|
EP |
|
A 2005-277711 |
|
Oct 2005 |
|
JP |
|
Primary Examiner: Lee; Benjamin C
Assistant Examiner: Shannon; Michael
Attorney, Agent or Firm: Oliff & Berridge, PLC
Claims
What is claimed is:
1. A power management system, comprising: an in-vehicle device
including an in-vehicle device controller that: transfers
connection information to a power management device, the connection
information indicating whether the in-vehicle device can
communicate with the power management device; and transfers
condition information to the power management device, the condition
information indicating that the in-vehicle device is ready for
turning off; or sets the in-vehicle device to not communicate with
the power management device when a predetermined condition is met,
the predetermined condition indicative of an inability of the
in-vehicle device to transfer information to the power management
device; and the power management device including a power
management controller that: requests the connection information
from the in-vehicle device; requests the condition information from
the in-vehicle device; and determines that the in-vehicle device is
ready for turning off when: both the connection information and the
condition information have been received from the in-vehicle
device; or no connection information has been received from the
in-vehicle device because the in-vehicle device has been set to not
communicate with the power management device.
2. The power management system of claim 1, wherein: either the
in-vehicle device controller or the power management controller:
counts a number of program resets executed by the in-vehicle
device; and determines whether a predetermined number of program
resets occurs during a predetermined time period; and the
predetermined condition is met when the predetermined number of
program resets occurs during the predetermined time period.
3. The power management system of claim 1, wherein: the power
management device further comprises a memory; and when the power
management device receives the connection information from the
in-vehicle device, an ID of the in-vehicle device is stored in the
memory indicating that the in-vehicle device has an ability to
transfer information to the power management device.
4. The power management system of claim 1, wherein the power
management controller periodically requests the connection
information from the in-vehicle device.
5. The power management system of claim 1, wherein the power
management controller: detects a power-on state of the in-vehicle
device; and when the power-on state is detected, requests the
connection information from the in-vehicle device.
6. A power management method, comprising: requesting connection
information from an in-vehicle device, the connection information
indicating whether the in-vehicle device can communicate with a
power management device; determining whether a predetermined
condition is met, the predetermined condition indicative of an
inability of the in-vehicle device to communicate with the power
management device; and if the in-vehicle device can communicate
with the power management device, transferring connection
information to the power management device; requesting condition
information from the in-vehicle device, the condition information
indicating that the in-vehicle device is ready for turning off;
determining that the in-vehicle device is ready for turning off
when: both the connection information and the condition information
have been received from the in-vehicle device; or no connection
information has been received from the in-vehicle device because
the predetermined condition is met.
7. The power management method of claim 6, further comprising:
counting a number of program resets executed by the in-vehicle
device; determining whether a predetermined number of program
resets occurs during a predetermined time period; and determining
that the predetermined condition is met when the predetermined
number of program resets occurs during the predetermined time
period.
8. The power management method of claim 6, further comprising:
storing an ID of the in-vehicle device in a memory when the power
management device receives the connection information from the
in-vehicle device, the stored ID indicating that the in-vehicle
device has an ability to transfer information to the power
management device.
9. The power management method of claim 6, further comprising
periodically requesting the connection information from the
in-vehicle device.
10. The power management method of claim 6, further comprising:
detecting a power-on-state of the in-vehicle device; and when the
power-on-state is detected, requesting the connection information
from the in-vehicle device.
11. One or more storage mediums storing a set of program
instructions executable by one or more data processing devices, the
instructions usable to implement the method of claim 6.
Description
INCORPORATION BY REFERENCE
The disclosure of Japanese Patent Application No. 2006-006527 filed
on Jan. 13, 2006, including the specification, drawings and
abstract thereof, is incorporated herein by reference in its
entirety.
BACKGROUND
1. Related Technical Fields
Related technical fields include power management systems, methods,
and programs for in-vehicle devices.
2. Description of the Related Art
Various types of in-vehicle devices have been mounted on vehicles
to make drivers and fellow passengers in the vehicle more
comfortable. For example, radio receivers for receiving AM
broadcast and FM broadcast, TV receivers for receiving telecast
signals and displaying an image, audio devices for playing an MD
and/or a CD, and/or navigation devices for providing driving
guidance for the vehicle may be mounted on the vehicle as
in-vehicle devices.
To transfer digital data such as digitized image data, audio data,
or computer data among the various types of in-vehicle devices
described above, large-capacity and high-speed communication is
required. Therefore, the introduction of an in-vehicle network to
transfer digital data even in a small space such as within the
vehicle has been proposed. For example, the MOST (Media Oriented
Systems Transport) system is an example of an in-vehicle network
(for example, Japanese Unexamined Patent Application Publication
No. 2005-277711). The MOST system has a cyclic network. Various
in-vehicle devices such as a navigation device, an audio device, a
radio receiver, and an AV amplifier are connected to each other via
the network. As a result; for example, digital data output from the
audio device is transferred to the AV amplifier through the network
and the signal input by the AV amplifier is amplified and output to
a speaker.
Further, the MOST system utilizes a network protocol using fiber
optics. Importantly, systems such as the MOST system control the
power of the entire system collectively instead of turning on/off
the power supplied to each of the in-vehicle devices in the system.
For example, each in-vehicle device and a power management unit for
controlling the power of the system are connected to each other
with an LAN or the MOST, and request data for turning on/off the
power supplied to each of the in-vehicle devices is transferred
from the power management unit, so that all of the connected
in-vehicle devices may be turned on or off.
SUMMARY
According to the power management system using the power management
unit described above, when a program reset repeatedly occurs in any
one of the in-vehicle devices, the power management unit recognizes
that a new in-vehicle device is connected to the power management
unit every time the program reset occurs. As a result, for each
recognized new connection, the power management system continuously
provides registration processing for such a newly connected
in-vehicle device. Typically, before the power management unit
turns each of the in-vehicle devices off, the power management unit
needs to receive responses that the connected in-vehicle devices
are ready for turning off from the connected in-vehicle devices and
needs to send request data to turn the in-vehicle devices off.
However, when the series of resets occurs as described above, the
reset in-vehicle device cannot send the response that the
in-vehicle device is ready for turning off. Further, because
registration processing for the in-vehicle device is repeatedly
executed by the power management unit, the power management unit
cannot send request data to turn the in-vehicle device off. As a
result, the power of the entire system cannot reliably be turned
off.
Various exemplary implementations of the broad principles described
herein provide systems, methods, and programs for turning the power
of the entire system off and preventing the battery of the vehicle
from running out even when a series of program reset occurs by some
sort of program factor or non-program factor.
Various exemplary implementations provide an in-vehicle device that
may transfer connection information to a power management device,
the connection information indicating whether the in-vehicle device
can communicate with the power management device. The in-vehicle
device may either transfer condition information to the power
management device, the condition information indicating that the
in-vehicle device is ready for turning off, or may set the
in-vehicle device to not communicate with the power management
device when a predetermined condition is met, the predetermined
condition indicative of an inability of the in-vehicle device to
transfer information to the power management device. The functions
of the in-vehicle device may be implemented by a method or
program.
Various exemplary implementations provide a power management device
that may request the connection information from the in-vehicle
device and may request the condition information from the
in-vehicle device. The power management device may determine that
the in-vehicle device is ready for turning off when both the
connection information and the condition information have been
received from the in-vehicle device. Alternatively, the power
management device may determine that the in-vehicle device is ready
for turning off when no connection information has been received
from the in-vehicle device because the in-vehicle device has been
set to not communicate with the power management device. The
functions of the power management device may be implemented by a
method or program.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary implementations will now be described with reference to
the accompanying drawings, wherein:
FIG. 1 is a structure outline of an exemplary power control
system;
FIG. 2 is a block diagram showing control structures of an
exemplary in-vehicle device and an exemplary communication
device;
FIG. 3 is a flowchart showing an exemplary reset method;
FIG. 4 is a flowchart showing an exemplary power management
method;
FIGS. 5A and 5B are diagrams showing exemplary recognition
processing; and
FIG. 6 is a flowchart showing an exemplary power management
method.
DETAILED DESCRIPTION OF EXEMPLARY IMPLEMENTATIONS
FIG. 1 is a diagram showing an exemplary structure of a power
control system 1. As shown in FIG. 1, the power control system 1
may include an in-vehicle network including a navigation
apparatus/device 2, a CD player 3, a radio tuner 4, and/or an AV
amplifier 5 as in-vehicle devices mounted in a vehicle. The power
control system 1 may also include a communication master device
(power management device) 6 for communicating and controlling each
of the in-vehicle apparatuses/devices 2-5. The power control system
1 may include a communication network 7 that circularly connects
each of the in-vehicle devices 2-5 and the communication master
device 6.
The communication network 7 may be, for example, a data
communication network including, for example, the MOST system. The
communication master device 6 may include a monitor device 9 for
displaying images and an input device 10, which has a plurality of
buttons, operated by a user.
The navigation device 2 may be an in-vehicle device for providing
route guidance to a destination set by the user. A GPS 11 may be
connected to the navigation device 2. The GPS 11 may receive
position information according to a current vehicle position. The
navigation device 2 may read out map information for the area
surrounding the current vehicle position from a memory such as an
internal CD, a DVD, or a hard disk drive on the basis of the
received position information and may transfer image data (map
data) to the monitor device 9 through a transmission line on the
basis of the read out information, so that the map and the current
vehicle position are displayed on the monitor device 9. The
navigation device 2 may transfer audio data of the route guidance
to the AV amplifier 5 through the communication network 7. The AV
amplifier 5 may amplify the input signal and a speaker 13 to output
an audio guidance.
The CD player 3 may be an audio device for playing a CD. The CD
player 3 may read out digital data from the CD and may transfer the
digital data to the AV amplifier 5 through the communication
network 7. The AV amplifier 5 may amplify the input signal and the
speaker 13 may output an audio message or music. The radio tuner 4
may be a receiver for receiving radio broadcasting. The radio tuner
4 may transfer a signal of an AM/FM broadcast received by an
antenna 14 to the AV amplifier 5 through the communication network
7. The AV amplifier 5 may amplifies the input signal and the
speaker 13 thereby output an audio message or music. The AV
amplifier 5 may be an amplifier for amplifying an input audio
signal and the speaker 13 may be connected to the AV amplifier 5.
The AV amplifier 5 may amplify digital data input from the
navigation device 2, the CD player 3, and/or the radio tuner 4
thereby output the digital data from the speaker 13.
The communication master device 6 may be a control device for
communicating with each of the in-vehicle devices 2-5 via the
communication network 7 and may control the in-vehicle devices 2-5.
The monitor device 9 and/or the input device 10 may be connected to
the communication master device 6. When the user operates the input
device 10, the communication master device 6 may request each
in-vehicle device 2-5 to start various programs on the basis of the
operation by the user. The communication master device 6 may store
image data in a memory, such as an internal storage device, and may
display various types of images corresponding to one or more of the
running in-vehicle devices (e.g., may not include the navigation
device 2) on the monitor device 9. For example, a title of a song
and/or the number of tracks may be displayed while the CD player 3
is running, and a frequency and/or a name of a radio station may be
displayed while the radio tuner is running.
The communication master device 6 may control, for example, the
power-on/off state of the in-vehicle devices 2-5. Specifically, a
key switch 15 may be connected to the communication master device 6
for turning on/off a vehicle ignition or an ACC (accessory). When
the ACC is on, the communication master device 6 may transfer a
data signal over the communication network 7 and may request the
in-vehicle devices 2-5 to turn on. When the ACC is off, the
communication master device 6 may stop transferring the data signal
over the communication network 7 and may request the in-vehicle
devices 2-5 to turn off. Note that a gateway ECU (electronic
control unit), as an interface for receiving a vehicle signal or a
diagnosis such as a CAN, may be connected to the communication
network 7 and the key switch 15 may be connected to the gateway
ECU.
Next, control structures of the in-vehicle devices 2-5 and the
communication master device 6 in the power control system 1
according to the first example will be described with reference to
FIG. 2. FIG. 2 is a diagram showing exemplary control structures of
the in-vehicle devices 2-5 and an exemplary communication master
device 6 that may be used in the power control system 1.
As shown in FIG. 2, the navigation device 2 may include a
navigation controller (ECU 21) and a current position detection
section 22. The navigation ECU 21 may include a CPU 31 as a
calculating device and a control device for controlling the entire
navigation device 2. The navigation ECU 21 may include a memory
such as a RAM 32, a ROM 33, and/or a flash memory 34. The RAM 32
may be used as a working memory when the CPU 31 executes various
calculations. Route data for a searched route, information
regarding a starting time of a series of program resets caused by a
program factor or a non-program factor, and a reset counter 35 for
counting the number of resets may be stored in the RAM 32.
The ROM 33 may store a control program, a series of reset
processing programs (for example, implementing the method shown in
FIG. 3) for setting an in-vehicle device not to respond to a
communication from the communication master device 6 and for
turning the in-vehicle device off when the series of resets occurs,
and a power management control program (for example, implementing
the method shown in FIG. 4) for controlling the power-on/off state
of the in-vehicle devices on the basis of the communication
provided by the communication master device 6. The flash memory 34
may store a program read out from the ROM 33. Note that, a
semiconductor memory or a magnetic core may be used as the RAM 32,
the ROM 33, or the flash memory 34. Further, an MPU may be used as
the calculating device and the control device instead of the CPU
31.
When the communication master device 6 sends a data signal through
the communication network 7 (for example, when it is ordered that
the navigation device 2 should be turned on), the navigation ECU 21
may control the navigation device 2 to turn on (for example,
implementing the method shown in FIG. 4). Meanwhile, when the
communication master device 6 stops transferring the data signal
(for example, when it is ordered that the navigation device 2 is
turned off), the navigation ECU 21 may control the navigation
device 2 to turn off. Further, when a series of program resets
occurs a predetermined number of times (for example, equal to or
more than 11 times) within a predetermined time period (for
example, 60 seconds) due to a program factor or a non-program
factor (for example, when a system reset occurs due to a hardware
error when accessing software), the navigation ECU 21 may sets the
in-vehicle device to not respond to the communication provided by
the communication master device 6 and may controls the navigation
device 2 to turn off (for example, implementing the method shown in
FIG. 3).
The current position detection section 22 may include the GPS 11
for detecting a current vehicle position and a current time by
receiving an electric wave provided by a satellite and a map
database (DB) 24 for storing map data, so that it may be possible
to specify the current vehicle position and the travel direction of
the vehicle on the map.
Next, the control structure of the communication master device 6
will be described with reference to FIG. 2. The communication
master device 6 may basically include a controller (communication
master ECU 40) and various types of additional devices such as, for
example, the monitor device 9, the input device 10, or the key
switch 15 connected to the communication master ECU 40.
The communication master ECU 40 may include a CPU 41 as a
calculating device and a control device for controlling the entire
communication master device 6 and a memory such as an RAM 42,
and/or an ROM 43. The RAM 42 may be used as a working memory when
the CPU 41 executes various calculations. The RAM 42 may store IDs
of in-vehicle devices, which respond to a connection
acknowledgement request among the in-vehicle devices 2-5. The ROM
43 may store a control program and a power management control
program (for example, implementing the method shown in FIG. 4) for
controlling the power-on/off state of the in-vehicle devices by
communicating with each of the in-vehicle devices connected to the
communication network 7. Note that, a semiconductor memory or a
magnetic core may be used as the RAM 42 or the ROM 43. Further, an
MPU may be used as the calculating device and the control device
instead of the CPU 41.
The communication master ECU 40 may send a connection
acknowledgement request to each of the in-vehicle devices 2-5 via
the communication network 7 and may store the IDs of the in-vehicle
devices that respond to the connection acknowledgment request among
the in-vehicle devices 2-5, so that the communication master ECU 40
may recognize which in-vehicle device is currently connected.
Further, when the ACC is on, the communication master ECU 40 may
start sending data signals over the communication network 7 and may
request each of the in-vehicle devices 2-5 to turn on. When the ACC
is off, the communication master ECU 40 may send a power-off
permission to each of the in-vehicle devices 2-5 via the
communication network 7. Then after all of the in-vehicle devices
which are currently connected to the communication master ECU 40
respond to the permission, the communication master ECU 40 may stop
sending data signals over the communication network 7 and requests
each of the in-vehicle devices 2-5 to turn off (for example,
implementing the method shown in FIG. 4).
The CD player 3 may include a controller (CD player ECU 25). The
radio tuner 4 may include a controller (radio tuner ECU 26). The AV
amplifier 5 may include a controller (AV amplifier controller ECU
27). Note that although the details of the CD player ECU 25, the
radio tuner ECU 26, and the AV amplifier ECU 27 are not described
here, each of the ECUs may include a CPU and an internal storage
device such as an RAM, an ROM, and/or a flash memory as in the case
of the navigation ECU 21. Further, the RAMs of these in-vehicle
devices may store a storage range for storing a starting time of a
series of program resets due to, for example, a program factor. A
reset counter for counting the number of resets may be included in
the RAMs. Further, in the ROMs, a series of reset processing
programs (for example, implementing the method shown in FIG. 3) and
a power management control program (for example, implementing the
method shown in FIG. 4) described later may be stored as in the
case of the navigation device.
Next, an exemplary reset method will be described with reference to
FIG. 3. The exemplary method may be implemented, for example, by
one or more components of the above-described system 1. However,
even though the exemplary structure of the above-described system 1
may be referenced in the description, it should be appreciated that
the structure is exemplary and the exemplary method need not be
limited by any of the above-described exemplary structure. For
example, the method may be stored in the form of a program in the
ROMs and/or the RAMs of the ECUs 21 and 25-27 and may be executed
by each of the CPUs of the ECUs 21 and 25-27 after the in-vehicle
devices corresponding to the ECUs are turned on.
The method may be embodied as a program for setting the in-vehicle
devices not to respond to the communication provided by the
communication master device 6 and for turning the in-vehicle
devices off when the series of program reset occurs due to a
program factor or a non-program factor (for example, when a system
reset occurs due to a hardware error when just accessing a
software).
As shown in FIG. 3, it is determined whether the method is properly
terminated without resetting in Step 1 (hereinafter referred to as
S1). Specifically, when an ACC off sequence run flag is set on a
procedure in S10 and when the power is properly turned off, it is
determined that the method is properly terminated.
When it is determined that the method is properly terminated
(S1=YES), the reset counter in the RAM is initialized and the
counter value (CT) is set as "0" (S2).
In S3, a current time T obtained by an RTC (Real Time Clock) is
stored, for example, by the CPU in the RAM. Note that, the current
time T stored in the RAM in S3 may be used in S15 as a starting
time of a series of resets while it is determined whether a
condition for turning off is met or not. In S4, a communication
control processing for responding to a connection acknowledgment
request provided by the communication master device 6 or for
receiving a request to start various types of control program is
executed.
In S5, the standard control processing for in-vehicle devices
corresponding to communication control processing in S4 is
executed. Specifically, for example, the navigation device 2 may
execute a destination setting processing, a route search
processing, and/or a guidance processing along the route on the
basis of the instruction from the communication master device 6.
Alternatively, for example, the CD player 3 may play a CD, pause
the CD, and/or fast-forward the CD on the basis of the instruction
from the communication master device 6.
In S6, it is determined whether the method is reset due to a
program factor or a non-program factor (for example, when a system
reset occurs due to a hardware error when accessing software). When
it is determined that the method is reset (S6=YES), the procedure
returns to S1. When it is determined that the method is not reset
(S6=NO), the procedure goes to S7.
In S7, it is determined whether the power-off permission sent from
the communication master device 6 is received. When it is
determined that the power-off permission is not received (S7=NO),
the procedure returns to S4 and various control processing is again
executed. When it is determined that the power-off permission is
received (S7=YES), a response to the power-off permission is sent
to the communication master device 6 and the communication master
device 6 is informed of the device being ready for turning off
(S8).
In S9, it is determined whether data signal transfer on the
communication network 7 is terminated, that is, whether the
communication master device 6 requests for turning the in-vehicle
device off. When it is determined that data signal transfer is not
terminated (S9=NO), the method does not progress until the data
signal transfer is terminated. When it is determined that data
signal transfer is terminated (S9=YES), the method goes to S10.
In S10, the ACC off sequence run flag is set on the basis of the
completion of the program. In S11, the CPU turns off the in-vehicle
device.
When it is determined that the program is not successfully
terminated in S1 (S1=NO), that is, it is determined that the
program is reset and crashed, the current time t obtained by the
RTC is stored in the RAM (S12). Note that, the current time t
stored in the RAM in S12 is used as a starting time of last reset
while it is determined whether the power-off condition is met in
S15. In S13, "1" is added for the reset counter value (CT) in the
RAM.
In S14, it is determined whether the count of the reset counter
(CT) in the RAM is 1, that is, whether the first program reset
occurs after the program is terminated. When it is determined that
the count of the reset counter (CT) in the RAM is 1 (S14=YES), the
procedure returns to S3 to store the starting time T of the series
of resets.
When it is determined that the count of the reset counter (CT) in
the RAM is other than 1 (S14=NO), it is further determined whether
the power-off condition is met (S15). The power-off condition here
means a condition to determine whether a response to the power-off
permission can be sent to the communication master device 6.
Specifically, the condition may be that the series of program
resets occurs a predetermined number of times (for example, equal
to or more than 11 times) within a predetermined time period (for
example, 60 seconds). Then, when "t<T+60 sec" is true according
to the starting time T of the series of resets stored in S3 or S18
and the starting time t of the last reset stored in S12, and when
the count of the reset counter (CT) is greater than 10 (CT>10),
it is determined that the power-off condition is met.
When it is determined that the power-off condition is met
(S15=YES), the in-vehicle device is set not to respond to the
communication provided by the communication master device 6 (S16)
and the procedures goes to S9. Note that, the in-vehicle device set
not to respond to the communication provided by the communication
master device 6 in S9 is not recognized by the communication master
device 6 as an in-vehicle device connected to the communication
network 7 (S25 in FIG. 4), so that even if any one of the
in-vehicle devices is repeatedly reset, the communication master
device 6 stops transferring a data signal and requests the entire
power control system 1 to turn off.
When it is determined that the power-off condition is not met
(S15=NO), it is further determined whether the count of the reset
counter CT is greater than 10 (CT>10), that is, whether it takes
equal to or more than 60 seconds for the in-vehicle device to be
repeatedly reset equal to or more than 11 times (S17).
As a result, when it is determined that the count of the reset
counter CT is greater than 10 (CT>10) (S17=YES), the CPU stores
the current time T obtained by the RTC to re-count the number of
the series of resets (S18). In S19, the CPU initializes the count
of the reset counter (CT) in the RAM and set the count as "1"
(S19). Then the procedure goes to S4. Note that, the current time T
stored in the RAM in S18 is used as a starting time of the series
of resets while it is determined whether the power-off condition is
met in S15.
When it is determined that the count of the reset counter (CT) is
equal to or less than 10 (CT>10) (S17=NO), that is, that the
number of the reset during the series of resets is less than 11
times since the number of times starts being counted, the
procedures goes to S4 and the number of reset is ongoingly
counted.
Next, an exemplary power management method will be described with
reference to FIG. 4. The exemplary method may be implemented, for
example, by one or more components of the above-described system 1.
However, even though the exemplary structure of the above-described
system 1 may be referenced in the description, it should be
appreciated that the structure is exemplary and the exemplary
method need not be limited by any of the above-described exemplary
structure.
For example, the method my be embodied as a program stored in the
ROM and/or the RAM of each of the ECUs 21, 25-27, and 40 and
executed by the communication master ECU 40 of the communication
master device 6 and the ECUs 21 and 25-27 of the in-vehicle
devices.
The first portion of the method, which, for example, may be
executed by the CPU 41 will be described. First, in S21, the CPU 41
determines whether the key switch 15 (ACC) is turned on. When it is
determined that the ACC is not on (S21=NO), the power management
processing method is terminated. When it is determined that the ACC
is on (S21=YES), the CPU 41 starts transferring a data signal over
the communication network 7 for turning on the power of the
in-vehicle device in S22. In S23, the CPU 41 transfers a connection
acknowledgement request to each of the in-vehicle devices 2-5
connected through the communication network 7.
In S24, the CPU 41 receives responses to the connection
acknowledgment request (sent in S23) from the in-vehicle devices.
In S25, IDs of in-vehicle devices, which responded to the
connection acknowledgment request among all of the in-vehicle
devices, are stored in the RAM 42. Therefore, it may be specified
which in-vehicle device is currently connected to the communication
master device 6. Then the CPU 41 executes system communication
processing such as a request for starting a control program for
each of the connected in-vehicle devices in S26.
In S27, the CPU 41 determines whether the key switch 15 (ACC) is
turned off. When it is determined that the ACC is not off (S27=NO),
the IDs of the in-vehicle devices stored in the RAM 42 in S25 are
initialized (S28), and the procedure returns to S23. Then the
connection acknowledgment request is again transferred and the IDs
of only in-vehicle devices that respond to the request are
stored.
As described above, the ECUs 21 and 25-27 of the in-vehicle devices
are set not to respond to the communication provided by the
communication master device 6 when the series of program resets
occurs a predetermined number of times within a predetermined time
period (S16 in FIG. 3). As a result, the in-vehicle devices which
are set not to respond to the communication provided by the
communication master device 6 do not respond to the connection
acknowledgement request, so that, in S25, the CPU 41 does not
recognize such in-vehicle devices as the in-vehicle devices
connected to the communication master device 6 (that is, the CPU 41
assumes that such in-vehicle devices do not exist).
The recognition processing of the in-vehicle devices that are
connected to the communication master device 6 is exemplified in
FIGS. 5A and 5B. When, for example, the navigation device 2, the CD
player 3, the radio tuner 4, and the AV amplifier 5 respond to the
connection acknowledgment request, the IDs of the in-vehicle
devices 2-5 are stored in the RAM 42 as shown in S25 in FIG. 5A.
The CPU 41 recognizes that the navigation device 2, the CD player
3, the radio tuner 4, and the AV amplifier 5 are connected to the
communication master device 6. When, for example, the navigation
device 2 is repeatedly reset and is set not to respond to the
communication provided by the communication master device 6 (S16 in
FIG. 3), the navigation device 2 will not respond to the connection
acknowledgement request. As a result, in S25, only the IDs of the
CD player 3, the radio tuner 4, and the AV amplifier 5 are stored
in the RAM 42 as shown in FIG. B. Thus, the CPU 41 recognizes that
only the CD player 3, the radio tuner 4, and the AV amplifier 5 are
connected to the communication master device 6.
When it is determined that the ACC is off in S27 (S27=YES), the CPU
41 sends the power-off permission to each of the in-vehicle devices
connected through the communication network 7 for determining
whether the in-vehicle devices are ready for turning off (S29).
In S30, the CPU 41 receives responses to the power-off permission
(sent from each of the in-vehicle devices in S29). In S31, it is
determined whether all expected responses to the power-off
permission are received from all in-vehicle devices, which
responded to the connection acknowledgement request in S25. For
example, when only the IDs of the CD player 3, the radio tuner 4,
and the AV amplifier 5 are stored in the RAM 42, the CPU 41
determines whether the responses to the power-off permission from
the CD player 3, the radio tuner 4, and the AV amplifier 5 are
received.
When it is determined that the responses to the power-off
permission from all of the in-vehicle devices which responded to
the connection acknowledgement request are not received (S31=NO),
the CPU 41 waits until receiving all responses to the power-off
permission. When it is determined that the all expected responses
to the power-off permission from the in-vehicle devices which
responded to the connection acknowledgement request are received
(S31=YES), the CPU 41 stops transferring the data signal over the
communication network 7 to turn the in-vehicle devices off (S32).
As a result, the in-vehicle devices connected to the communication
network 7 are turned off.
Next, the portions of the method that, for example, may be executed
by the CPUs of the in-vehicle devices 2-5 connected to the
communication master device 6 will be described.
In S41, the CPU determines whether the data signal sent from the
communication master device 6 is received. When it is determined
that the data signal is received (S41=YES), the in-vehicle device
is turned on (S42). When it is determined that the data signal is
not received (S41=NO), the power management processing method is
terminated.
Another control processing is executed for the in-vehicle device in
S43. Specifically, for example, according to the navigation device
2, a destination setting processing, a route search processing,
and/or a route guidance processing along the set route may be
executed on the basis of the request from the communication master
device 6. According to the CD player 3, a CD playing processing, a
pausing processing, and/or a fast-forwarding processing may be
executed on the basis of the request from the communication master
device 6.
In S44, the connection acknowledgement request sent from the
communication master device 6 is received. In S45, the response to
the connection acknowledgement request is sent to the communication
master device 6, so that the communication master device 6 may
specify which in-vehicle device is currently connected to the
communication master device 6.
In S46, the power-off permission sent from the communication master
device 6 is received. In S47, the response to the power-off
permission is sent to the communication master device 6, so that
the communication master device 6 may determine whether the
currently connected in-vehicle device is ready for turning off.
In S48, the CPU determines whether the data signal is no longer
transferred from the communication master device 6. When it is
determined that the data signal is no longer transferred (S48=YES),
the corresponding in-vehicle device is turned off (S49). When it is
determined that the data signal is still transferred, (S48=NO), the
CPU waits until the transfer of the data signal stops.
As described in detail above, according to the power control system
1, when it is determined that any one of the in-vehicle devices
(the navigation device 2, the CD player 3, the radio tuner 4, and
the AV amplifier 5) connected to the communication master device 6
is repeatedly reset and that the corresponding program is reset a
predetermined number of times (for example, equal to or more than
11 times) within a predetermined time period (for example, 60
seconds) (S15=YES), the in-vehicle device is set not to respond to
the communication provided by the communication master device 6
(S16). Meanwhile, when the communication master device 6 recognizes
in-vehicle devices which responded to the connection
acknowledgement request as currently connected in-vehicle devices
(S25) and when it is determined that all expected responses to the
power-off permission from all of the currently connected in-vehicle
devices are received (S31=YES), the communication master device 6
requests the in-vehicle devices to turn off (S32).
Therefore, even if a series of program resets occurs by some sort
of program factor or non-program factor (for example, when a system
reset occurs due to a hardware error when accessing software. e.g.,
a crash) and there is an in-vehicle device which does not send
condition information indicating that the in-vehicle device is
ready for turning off to the power management device, the power
management system ignores the existence of such in-vehicle device.
As a result, the power of the entire system may be turned off in
spite of the system reset. As a result, the in-vehicle devices will
not remain on after the vehicle engine stops, thereby conserving
the power of the vehicle's battery.
Another exemplary power management method will be described with
reference to FIG. 6. Again, the exemplary method may be
implemented, for example, by one or more components of the
above-described system 1. However, even though the exemplary
structure of the above-described system 1 may be referenced in the
description, it should be appreciated that the structure is
exemplary and the exemplary method need not be limited by any of
the above-described exemplary structure.
There may be a difference between the power control system 1 and
the power control system that may execute the method of FIG. 6. The
power control system that may execute the method of FIG. 6, may
initialize IDs of in-vehicle devices stored in the RAM 42 of the
communication master device 6 only when it is determined that a new
in-vehicle device is connected and re-recognizes which in-vehicle
device is connected to the communication master device 6.
The method of FIG. 6 may be implemented by a program stored in the
ROM and/or the RAM of the ECUs 21, 25-27, and 40 and may be
repeatedly executed by the CPUs in certain intervals.
The first portion of the method, which, for example, may be
executed by the CPU 41 will be described. First, in S101, the CPU
41 determines whether the key switch 15 is turned ACC on. When it
is determined that the ACC is not on (S101=NO), the power
management processing method is terminated.
When it is determined that the ACC is on (S101=YES), the CPU 41
starts transferring a data signal over the communication network 7
to request the in-vehicle devices to turn on in S102. In S103, the
CPU 41 sends the connection acknowledgement request to each of the
in-vehicle devices (for example, the navigation device 2, the CD
player 3, the radio tuner 4, and the AV amplifier 5) connected
through the communication network 7.
In S104, the CPU 41 receives responses to the request in S103 sent
from the in-vehicle devices. In S105, the IDs of the in-vehicle
devices which responded to the request among all of the in-vehicle
devices are stored in the RAM 42, so that it may be specified which
in-vehicle device is currently connected to the communication
master device 6.
In S106, the CPU 41 determines whether any in-vehicle device, which
is newly connected to the communication network 7, is detected.
When the program reset occurs according to the in-vehicle device
connected to the communication network 7, the response to the
connection acknowledgement request is sent to the communication
master device 6 again to inform the connection of the in-vehicle
device. Therefore, when the program of any one of the in-vehicle
devices 2-5 connected to the communication master device 6 is
reset, the communication master device 6 detects the new connection
of the in-vehicle device.
When it is determined that the connection of the new in-vehicle
device is detected (S106=YES), the IDs of the in-vehicle devices
stored in the RAM 42 in S105 are initialized (S107), and the
procedure returns to S103. The connection acknowledgement request
is again sent and the IDs of the in-vehicle devices, which
responded to the request, are registered.
When it is determined that the connection of the new in-vehicle
device is not detected (S106=NO), a system communication processing
such as a request for starting control programs for the connected
in-vehicle devices is executed (S108).
In S109, the CPU 41 determines whether the key switch 15 is turned
ACC off. When the ACC is not off (S109=NO), the procedure returns
to the determination processing in S106 and it is further
determined whether there is any in-vehicle device which is newly
connected.
When it is determined that the ACC is off (S109=YES), the power-off
permission is sent to each of the in-vehicle devices (for example,
the navigation device 2, the CD player 3, the radio tuner 4, and
the AV amplifier 5) connected through the communication network 7
for determining whether such in-vehicle devices are ready for
turning off (S110).
In S111, the CPU 41 receives the responses to the power-off
permission in S110 sent from each of the in-vehicle devices. In
S112, it is determined whether all expected responses to the
power-off permission from all of the in-vehicle devices, which
responded to the connection acknowledgement request in S105, are
received. For example, when the IDs of the CD player 3, the radio
tuner 4, and the AV amplifier 5 other than the navigation device 2
are stored in the RAM 42, the CPU 41 determines whether the
responses to the power-off permissions from the CD player 3, the
radio tuner 4, and the AV amplifier 5 are received.
When it is determined that all expected responses to the power-off
permission from all of the in-vehicle devices which responded to
the connection acknowledgement request are not received (S112=NO),
the CPU 41 waits until all expected responses are received. When it
is determined that all responses to the power-off permission from
all of the in-vehicle devices which responded to the connection
acknowledgement request are received (S112=YES), the data signal
transfer over the communication network 7 stops to make the
in-vehicle devices turn off (S113), so that the in-vehicle devices
connected to the communication network 7 are controlled to turn
off.
Note that, processing described in S121-S129, for example, executed
by the CPUs of the in-vehicle devices 2-5 connected to the
communication master device 6 according to the power management
processing program is same as the processing described in S41-S49
executed by the CPUs of the in-vehicle devices 2-5 according to the
power management method of FIG. 4. Thus, a detail description
thereof is not repeated.
As described above, when it is determined that any one of the
in-vehicle devices 2-5 connected to the communication master device
6 is repeatedly reset and that the program of the in-vehicle device
is reset a predetermined number of times (for example, equal to or
more than 11 times) within a predetermined time period (for
example, 60 seconds), the in-vehicle device may be set not to
respond to the communication provided by the communication master
device 6. When the communication master device 6 recognizes only
in-vehicle devices which responded to the connection
acknowledgement request as the currently connected in-vehicle
devices (S105) and when it is determined that all expected
responses to the power-off permission from the connected in-vehicle
devices are received (S112=YES), the communication master device 6
requests the in-vehicle devices to turn of (S113). Therefore, even
if a series of program resets occurs by some sort of program factor
or non-program factor (for example, when a system reset occurs due
to a hardware error when accessing software) and there is an
in-vehicle device which does not send condition information
indicating that the in-vehicle device is ready for turning off to
the power management device, the power management system ignores
the existence of such in-vehicle device. Thus, the power of the
entire system may be turned off. As a result, the power-on state of
the in-vehicle devices may not continue after the vehicle engine
stops and it may conserve the power of the vehicle's battery.
While various features have been described in conjunction with the
examples outlined above, various alternatives, modifications,
variations, and/or improvements of those features and/or examples
may be possible. Accordingly, the examples, as set forth above, are
intended to be illustrative. Various changes may be made without
departing from the broad spirit and scope of the underlying
principles.
For example, according to the first and the second examples, the
navigation device 2, the CD player 3, the radio tuner 4, and the AV
amplifier 5 are described as the in-vehicle devices mounted in the
vehicle. However, such in-vehicle devices used in the power control
system 1 are not limited to the particular devices described above.
For example, an MD player, a DVD player, an ETC device, or any
other device requiring power may be used.
Further, according to the above examples, the power-off condition
to not respond to the communication provided by the communication
master device 6 is when the in-vehicle device is reset a
predetermined number of times within a predetermined time period.
However, if it is possible to determine that the in-vehicle devices
cannot respond to the power-off permission to the communication
master device 6 based on other conditions. For example, the
condition may be only that the program is reset a predetermined
number of times.
Further, according to the above examples, the system in which the
communication master device 6 and the in-vehicle devices 2-5 are
connected to each other through the MOST is described as an example
of the power control system for in-vehicle devices. However, any
system in which the communication master device 6 and the
in-vehicle devices 2-5 are connected to each other may be used. For
example, a system in which the communication master device 6 and
the in-vehicle devices 2-5 are connected to each other through the
LAN may be used. Further, as a communication method, an optical
communication with the fiber, an electric communication with an
electric signal, or a radio communication may be used.
* * * * *